How to convert an old speaker with a power amplifier at home into a Bluetooth speaker?

You can use the finished Bluetooth game board (module) to improve your hands-on ability, and kill two birds with one stone with old things. But the final cost and appearance will be different from the finished Bluetooth case. The finished Bluetooth speakers mostly use small-caliber, long-stroke speakers and digital power amplifiers, and the sound sounds heavy, which is actually a kind of rendering. Small-caliber speakers can never compare with large-caliber speakers. However, because of its small size, exquisite appearance, rechargeable, portable and even intelligent system, it is deeply loved by the public.

If the speaker at hand is an active speaker (built-in amplifier), then you only need a simple Bluetooth player board. If it is a passive speaker (there is no power amplifier inside), then choose a Bluetooth board with power amplifier. The picture below shows the Bluetooth module without power amplifier. ?

The picture above shows a USB flash drive, FM radio, App control and external sound card function. It can be said that it is a fully functional motherboard. It is also very simple to use. The power supply port can be directly powered by mobile phone charger or 5v, and the audio output is output by 3.5mm socket. If you are too lazy to start welding, buy a recording cable and connect the audio input of the active speaker. I have to say that with the development of science and technology, the price of electronic products is getting lower and lower! And many circuits are sold with finished boards, which are simpler and more convenient to use. ?

The picture above shows the Bluetooth player board with power amplifier module, which is suitable for refitting passive speakers. Open a hole in the appropriate position of the speaker, bring your own panel and embed the speaker.

Easy to use, simple wiring. Because the power amplifier is slightly smaller (5 watt digital power amplifier), it is suitable for speakers with high sensitivity, and the impedance is preferably 4 ohms, so the power can be higher. The voltage of the card in the above picture is wide, which can be used for 4-40v, and can also be used with the idle lithium battery of the mobile phone to realize the portable function.